/biz/ - Business & Finance

>>12295366
I think there is a monty hall thing going on with the second part. First is clearly 50%.
G -> G
G -> B
B -> G
B -> B
Lower two are eliminated since we know the oldest is a girl.
G -> G
G -> B
Since we don't know if the daughter answering the door is younger or older the above possibility has a 100% rate of showing girl while the below has a 50% rate of showing girl. Like the balls puzzle this means 2/3 chance the other daughter is a girl or 50% for part 1 of the question, 66.7% for part 2.

Of course this is disregarding the 90quintillion possible genders.